Phase 3 trial data shows experimental monoclonal antibody not to be efficacious.
Recent data from a Phase 3, randomized, placebo-controlled clinical trial that tested the investigative monoclonal antibody LY-CoV555 in hospitalized patients with the coronavirus disease 2019 (COVID-19), showed preliminary results that it did not provide any clinical benefit in comparison to a placebo. The findings were published in The New England Journal of Medicine.
The antibody was first uncovered by the Vancouver based company AbCellera Biologics, who were working in collaboration with the National Institute of Allergy and Infectious Disease (NIAID). Lilly Research Laboratories, Eli Lilly and Company then partnered with AbCellera to develop and manufacture the therapy.
The trial, named ACTIV-3, employed a master protocol which was designed to allow the study of multiple investigational agents for those who were hospitalized with COVID-19. The participants in the study were randomly assigned to receive a placebo or LY-CoV555, and all of them were also given the current standard of care. After the first 5 days of enrollment, the participants clinical status was assessed using an ordinal scale and followed for 90 days to assess recovery, which is defined as discharge from hospital, alive and being home for 14 days.
On October 26th, the trial stopped accepting new enrollees due to the Data and Safety Monitoring Board(DSMB) making a recommendation after reviewing stage 1 data that no further participants should be randomized to receive the investigational agent and that the investigators be unblinded to the data. The DSMB made this recommendation based on a low likelihood of clinical value in the population being analyzed. The study was closed with a total of 326 participants, of which 314 were randomized to receive the agent.
50% of those who received LY-CoV555 and 54% of the placebo recipients were in one of the two most favorable outcome categories after 5 days. This forced the investigators to come to the conclusion that LY-CoV555 did not accelerate the improvement of hospitalized COVID-19 patients more than the placebo group. Another important finding showed that there was no difference in the primary outcome between the two groups.